Ottawa River levels expected to plateau over the weekend

The management and monitoring board for the Ottawa River says its slow rise should plateau over the weekend and that the amount of rain that falls in the region will play a big role in what happens next.

The snowmelt has led to major flood levels around Lac Coulongenear Whitewater Region in eastern Ontario and Mansfield-et-Pontefract, Que., according to the latestOttawa River Regulation Planning Board update Thursday afternoon.

The major flood designation indicates that one or more streets are beginning to flood and several houses, buildings or neighbourhoods will be affected.

The board said the river is slowlyapproaching major flood levels downstream from there, from the Arnprior, Ont., area to the Montreal area.

"Levels are expected to stabilize over the weekend," the board wrote. "Rain over the weekend may result in additional level increases in some locations starting Monday, depending on the amount and location of rainfall."

The board maintains that water levels should remain well belowhistoric highs, many of themset during devastating floods in 2017 and 2019.

At Lac Coulonge, for example, the water was recorded at108.06metres above sea level Thursday afternoon.

That's well over a metre more thanits average for April 20,and a centimetre more than the highest reading ever for that date, but still more than onemetre from where waters peaked in mid-May 2019.

Less risk in Gatineau

The City of Gatineau is nowexpecting a lower risk to residences than originally projected but peak water levelcould last for one or two weeks once it is achieved, the city said in a news release.

About 30 residences and more than 300 lots are currently believed to be at risk of flooding there Friday night.

The city continues to give out sand, bags and prefilled sandbags at seven locations. Parts of the Gatineau and Masson-Angers sectors are consideredmost at risk.

The City of Ottawa said Thursday that this flooding is the type that typically happens once a decade, compared to the once-in-a-century flood in 2019.

It's making portable toilets and water available for Constance Bay and Fitzroy Harbour residents who have lost water in their homes. Sandbags are available at nearly 30 locations.

Clarence-Rockland has set up three sandbagging stations.

The rise to come

Local conservationauthorities have said areas such as Chats Lake, Constance Bay, Britannia/Lac Deschnes, Cumberland, Clarence-Rockland andthe Township of Alfred and Plantagenet are prone to flooding in these conditions.

Compared to where they were Thursday morning, water levels in the following areas of concern were expected to rise by between 15 and 45 centimetres:

• Constance Bay: 15 centimetreswithin the next day and then stable for four or five days.
• Grandview Road andBelltownin the Britannia area: 20 centimetresover the next two to three days.
• Boise Village, Morin Road andLeo Lane in Cumberland: 25 centimetres over the next two to three days.
• Rockland: 45 centimetres over the next two to three days.
• Hawkesbury: 40 centimetres over the next two to three days.

There are also flood warnings for the Bobs and Christie lake areas, where water levels have stabilized,and the Little Mississippi, Madawaska, Opeongo and York rivers.

The Madawaska River Bridge in the Township of South Algonquin, Ont., has reopened to passenger vehicles.

Preparations continue

Students at West Carleton Secondary School in rural west Ottawaare one of manygroups of volunteers across the region helping fill sandbags in preparation for peak water levels.

Before the end of the school day Thursday, students packed 11,000 bagsto be shipped out to other groups of volunteersbuilding protective walls by the shoreline.

"I don't live in a flood risk area but I know a bunch of people who do: family, friends, school friends," Grade 11 student Cole Larue said. "I'm just trying to help and do my part."

Knoxdale-Merivale Coun. Sean Devinealso helped residents line their properties with sandbags Thursday.

Devine said he faces challenges getting people mobilized to help out, whether volunteers or public sector workers.

"When I get these wet boots off and I go back and put on my councillor clothes, that's one of the things I'd like to start taking a peek at," Devine said.

"How can I put in place long-term measures to address what is likely to be an ongoing concern?"

The Ottawa River Regulation Planning Board is scheduled to release its next update on river conditions Friday at 5 p.m. ET.